Nina Dobrev and Ian Somerhalder accept the award for favorite on-screen chemistry for their show "The Vampire Diaries"
IN PHOTO: Nina Dobrev and Ian Somerhalder accept the award for favorite on-screen chemistry for their show "The Vampire Diaries" at the 2014 People's Choice Awards in Los Angeles, California January 8, 2014. REUTERS/Mario Anzuoni

"The Vampire Diaries" already has interesting characters but the villains spice things up in the CW TV series. Listed below are just six of the TVD villains in six seasons that caused trouble or wanted to kill the Mystic Falls gang.

1. Klaus Mikaelson - The Original hybrid.

The TVD fans will certainly agree that Klaus Mikaelson is the best villain in "The Vampire Diaries" with his ruthless and compelling ways. The Original hybrid caused a lot of trouble for the Mystic Falls gang especially when the rest of his family members arrived in town.

A video shared on YouTube showed that it is not a good idea to make an Original hybrid angry or deny him of what he wants. Click HERE to watch the video clip from "The Vampire Diaries" Season 3, episode 21 titled "Before Sunset."

2. Katherine Pierce/Katerina Petrova - The Evil Doppelganger.

The villain character made a memorable first appearance in "The Vampire Diaries" Season 2, episode 1 titled "The Return." In the video clip shared, Katherine pretended to be Elena Gilbert (Nina Dobrev) but eventually revealed her true evil identity to John Gilbert (David Anders) when she chopped off his finger while having a conversation in the kitchen. Have a look at the video below.

Katherine's (Nina Dobrev) return also caused a lot of trouble for Elena. However, it all ended in "The Vampire Diaries" Season 5, episode 15 titled "Gone Girl" when Stefan (Paul Wesley) killed the evil doppelganger with the Traveler's knife while inhabiting Elena's body.

Credit: YouTube/VampiresWorldblogcz

3. Kai - The Psychotic Magic Sucker.

At the moment, Kai (Chris Wood) sits on the TVD's "Big Bad" and "Worst Sibling" throne. Season 6 introduced the psychotic witch that does not have any hesitation when it comes to hurting or killing his siblings and absorbs magic in order to gain power. In the mid-season finale, Kai became a powerful witch after sucking all of the magic from the Traveler's anti-magic border spell over Mystic Falls. Have a look at the video below.

Credit: YouTube/ChasingScenes

4. Connor Jordan - The Vampire Hunter.

In "The Vampire Diaries" Season 4, episode 2 titled "Memorial," the supernatural creatures of Mystic Falls had to deal with a vampire hunter who wants them dead after the members of the Council died from an explosion. A video clip shared on YouTube showed vampire hunter Connor Jordan (Todd Williams) trapping and trying to kill the vampires in Mystic Falls during Pastor Young's memorial service. Click HERE to watch the video.

5. Qetsiyah - The Scorned Traveler.

The appearance of Qetsiyah (Janina Gavankar) in "The Vampire Diaries" Season 5 conveyed the phrase "Hell hath no fury like a woman scorned." When her true love Silas (Paul Wesley) betrayed her and broke her heart because of Amara (Nina Dobrev), Qetsiyah made sure that she will get her revenge.

A flashback scene in "The Vampire Diaries" Season 5, episode 3 titled "Original Sin" showed how Qetsiyah got back at Silas. The powerful Traveler killed Amara and told Silas about it. Watch the video below.

Credit: YouTube/Team Salvatore

6. Enzo - The Augustine Vampire.

Enzo's (Michael Malarkey) desire to destroy Stefan's (Paul Wesley) happiness in "The Vampire Diaries" Season 6 is making the Augustine vampire an evil character. Enzo admitted in the mid-season finale episode titled "Christmas Through Your Eyes" that he is jealous of Stefan's life and he even has Matt (Zach Roerig) reluctantly helping him with his plan against the younger Salvatore vampire. Have a look at the video below of Enzo telling Matt (Zach Roerig) about his jealousy issues in "The Vampire Diaries" Season 6, episode 10.

Credit: YouTube/ChasingScenes

"The Vampire Diaries" Season 6 is scheduled to return with episode 11 titled "Woke Up With a Monster" on Jan. 22, 2015 at 8 p.m. ET on the CW Network.

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